Blood pressure is one index for analyzing cardiovascular disease. Performing a risk analysis for cardiovascular disease based on blood pressure is effective in preventing cardiovascular-related conditions such as stroke, heart failure, and myocardial infarction. In particular, morning hypertension, in which the blood pressure rises in the early morning, is related to heart disease, stroke, and the like. Furthermore, among morning hypertension symptoms, the symptom called “morning surge”, in which the blood pressure rapidly rises within one hour to one and a half hours after waking up, has been found to have a causal relationship with stroke. Accordingly, understanding the interrelationship between time (lifestyle) and changes in blood pressure is useful in risk analysis for cardiovascular-related conditions. It is therefore necessary to continuously measure blood pressure over a long period of time.
Furthermore, recent study results have shown that home blood pressure, which is blood pressure measured at home, is more effective in the prevention, diagnosis, treatment, and so on of cardiovascular-related conditions than blood pressure measured at a hospital or during a health examination (casual blood pressure). Accordingly, blood pressure meters for home use have become widely prevalent, and home blood pressure values have started to become used in diagnoses; thus various types of blood pressure meters for home use have been produced.
In a typical electronic blood pressure meter, a manchette containing an air bladder is uniformly wrapped around a part of a body, and changes in the volume of an arterial vessel pressurized by inflating/deflating the air bladder with air is obtained as changes in the amplitude of the pressure in the air bladder (a cuff pressure); meanwhile, electronic blood pressure meters that employ an oscillometric method for calculating blood pressure are in use, and the air bladder can be inflated using a piezoelectric pump, as disclosed in JP 2009-74418A, for example.